1. Field of the Invention
The present invention relates to a coil type unit for wireless power transmission, a wireless power transmission device, an electronic device, and a manufacturing method of a coil type unit for wireless power transmission.
2. Description of the Related Art
In recent times, a wireless power transmission system has been studied to charge a secondary battery embedded in a mobile terminal etc.
In general, the wireless power transmission device includes a wireless power transmission device that transmits power and a wireless power reception device that receives and stores power.
The wireless power transmission device transmits and receives power using electromagnetic induction. For this, a coil is provided inside the wireless power transmission device.
The coil provided at this time is a coil that electrically connects a plurality of coil patterns through a via-hole, but the thickness of the coil is increased and there are problems in terms of cost due to the plurality of coil patterns. Thus, recently, a coil having a single-layered coil pattern has been used.
However, in case of the single-layered coil pattern, since the output wiring coil should pass over the wound coil wiring for electrical connection between an inner end and an outer end of the coil, the overall thickness of the coil becomes double.
Therefore, since the overall thickness of the coil is increased and wiring forming and bonding processes for electrical connection are added, process costs are increased and manufacturing becomes inconvenient.
Therefore, in order to meet the current trend for thinner devices, there is a need for the development of a thinner coil type unit for wireless power transmission and a wireless power transmission device and an electronic device including the same.